Thorlabs FEL1100 Longpass Filter

The Thorlabs FEL1100 Longpass Filter is a precision optical longpass filter designed for near-infrared applications. It features a diameter of 25.0 mm and a cut-on wavelength of 1100 nm, meaning wavelengths longer than 1100 nm are transmitted while shorter wavelengths are effectively rejected. This optical element is ideal for imaging, spectroscopy, and laser systems where suppression of sub-1100 nm light is required. The filter substrate is made of high-quality UV fused silica with a coated longpass surface to ensure reliable performance and durability in scientific and industrial optical setups. Typical specifications include a clear aperture suited for Ø25 mm mounts and effective blocking of unwanted shorter wavelengths.

Applications: NIR filtering in optical benches, imaging systems, laser diagnostics, photonics experiments.